Year including construction (constant 2010 US$) 1991 11583.0510418739 1992 10156.0863516837 1993 8991.14289892322 1994 8535.74185948772 1995 7965.53405728914 1996 7686.65876367318 1997 7312.30673569238 1998 7656.9919964406 1999 7993.11451196915 2000 7943.55260549181 2001 7773.68747758425 2002 7920.22026272105 2003 7496.79962288524 2004 7141.86126202677 2005 7781.75439949198 2006 7766.16006712899 2007 7605.61803704667 2008 7512.48456720287 2009 7271.91598639823 2010 6947.78294130918 2011 6759.41748196634 2012 6628.93023089477 2013 6637.0156484652 2014 6543.73571590879 2015 6947.28227489638 2016 6964.71503406741 2017 6836.13377477814 2018 6867.04909510259